name: duk_call

proto: |
  void duk_call(duk_context *ctx, duk_idx_t nargs);

stack: |
  [ ... func! arg1! ...! argN! ] -> [ ... retval! ]

summary: |
  <p>Call target function <code>func</code> with <code>nargs</code> arguments
  (not counting the function itself).  The function and its arguments
  are replaced by a single return value.  An error thrown during the
  function call is not automatically caught.
  </p>

  <p>The target function <code>this</code> binding is initially set to
  <code>undefined</code>.  If the target function is not strict, the binding
  is replaced by the global object before the function is invoked; see
  <a href="http://www.ecma-international.org/ecma-262/5.1/#sec-10.4.3">Entering Function Code</a>.
  If you want to control the <code>this</code> binding, you can use
  <code><a href="#duk_call_method">duk_call_method()</a></code> or
  <code><a href="#duk_call_prop">duk_call_prop()</a></code> instead.</p>

  <p>This API call is equivalent to:</p>
  <pre class="ecmascript-code">
  var retval = func(arg1, ..., argN);
  </pre>

  <p>or:</p>
  <pre class="ecmascript-code">
  var retval = func.call(undefined, arg1, ..., argN);
  </pre>

example: |
  /* Assume target function is already on stack at func_idx; the target
   * function adds arguments and returns the result.
   */
  duk_idx_t func_idx = /* ... */;

  duk_dup(ctx, func_idx);
  duk_push_int(ctx, 2);
  duk_push_int(ctx, 3);
  duk_call(ctx, 2);  /* [ ... func 2 3 ] -> [ 5 ] */
  printf("2+3=%ld\n", (long) duk_get_int(ctx, -1));
  duk_pop(ctx);

tags:
  - call

seealso:
  - duk_call_method
  - duk_call_prop

introduced: 1.0.0